title: Amino acid sequence variations of signaling lymphocyte activation molecule and mortality caused by morbillivirus infection in cetaceans.
abstract: Morbillivirus infection is a severe threat to marine mammals. Mass die-offs caused by this infection have repeatedly occurred in bottlenose dolphins (Turiops truncatus) and striped dolphins (Stenella coeruleoalba), both of which belong to the family Delphinidae, but not in other cetaceans. However, it is unknown whether sensitivity to the virus varies among cetacean species. The signaling lymphocyte activation molecule (SLAM) is a receptor on host cells that allows morbillivirus invasion and propagation. Its immunoguloblin variable domain-like (V) region provides an interface for the virus hemagglutinin (H) protein. In this study, variations in the amino acid residues of the V region of 26 cetacean species, covering almost all cetacean genera, were examined. Three-dimensional (3D) models of them were generated in a homology model using the crystal structure of the marmoset SLAM and measles virus H protein complex as a template. The 3D models showed 32 amino acid residues on the interface that possibly bind the morbillivirus. Among the cetacean species studied, variations were found at six of the residues. Bottlenose and striped dolphins have substitutions at five positions (E68G, I74V, R90H, V126I, and Q130H) compared with those of baleen whales. Three residues (at positions 68, 90 and 130) were found to alternate electric charges, possibly causing changes in affinity for the virus. This study shows a new approach based on receptor structure for assessing potential vulnerability to viral infection. This method may be useful for assessing the risk of morbillivirus infection in wildlife.
authors.affiliation: Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima-cho, Yokosuka, 237-0061.
authors.forename: Yui
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Kazue
authors.initials: K
authors.lastname: Ohishi
authors.forename: Rintaro
authors.initials: R
authors.lastname: Suzuki
authors.forename: Yuko
authors.initials: Y
authors.lastname: Tajima
authors.forename: Tadasu
authors.initials: T
authors.lastname: Yamada
authors.forename: Yuka
authors.initials: Y
authors.lastname: Kakizoe
authors.forename: Takeharu
authors.initials: T
authors.lastname: Bando
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Fujise
authors.forename: Hajime
authors.initials: H
authors.lastname: Taru
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Murayama
authors.forename: Tadashi
authors.initials: T
authors.lastname: Maruyama
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015703:Antigens, CD / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D014644:Genetic Variation; D008969:Molecular Sequence Data; D018103:Morbillivirus / Q000502:physiology*; D018185:Morbillivirus Infections / Q000235:genetics / Q000401:mortality / Q000662:veterinary* / Q000821:virology; D010802:Phylogeny; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D016415:Sequence Alignment; D000071177:Signaling Lymphocytic Activation Molecule Family Member 1; D014907:Whales / Q000145:classification / Q000235:genetics* / Q000276:immunology / Q000821:virology
chemical_list: D015703:Antigens, CD; D011956:Receptors, Cell Surface; D000071177:Signaling Lymphocytic Activation Molecule Family Member 1
keywords: cetacean; morbillivirus; receptor; signaling lymphocyte activation molecule